The Textbook Things Gone Wrong in IT Thread

But just so it's out there: http://www.newegg.com/Product/Product.aspx?Item=N82E16817994147

and 6 of these http://www.newegg.com/Product/Product.aspx?Item=N82E16820147362

You are short a drive, you'd need seven not six for 6TB. But those prices are $100 too high for that drive anyway.

That hardware isn't useful, that's a consumer backplane. I priced out an actually enterprise Dell server for the drives and seven of them with RAID overhead handled. Real enterprise grade storage, $3,400.

DustinB3403

I know it's a consumer grade unit, but the unit has 1 internal bay for "Backup" making it 7 (even though that would be stupid as all gitup).

Which is still not worth it to dig any further for a 6TB SSD NAS.

DustinB3403

And if we wanted a true 6TB of usable space in RAID10, we'd need 12 drives.

scottalanmiller

@DustinB3403 said:

I know it's a consumer grade unit, but the unit has 1 internal bay for "Backup" making it 7 (even though that would be stupid as all gitup).

But it isn't a NAS chassis, it's only a drive holder. It's not a usable device on its own. It's not applicable at all. That isn't what a NAS is.

The number of bays is one issue, the number of drives though for pricing needs to be 7.

DustinB3403

Which the MSP is again recommending RAID5. . . . ... . .

scottalanmiller

@DustinB3403 said:

And if we wanted a true 6TB of usable space in RAID10, we'd need 12 drives.

But you don't use RAID 10 on SSD, you use RAID 5. So seven. Trust me, I just went through all of this to figure out what an enterprise storage unit would look like for this use case. $3,400, after RAID. I've been quite clear that I accounted for all of that.

DustinB3403

Why wouldn't you use RAID10 with SSD's? I must've missed the article.

scottalanmiller

@DustinB3403 said:

Which the MSP is again recommending RAID5. . . . ... . .

But on spinning rust, which alone should have them fired. RAID 5 on spinning drives in unthinkable. On SSD it would be sensible.

scottalanmiller

@DustinB3403 said:

Why wouldn't you use RAID10 with SSD's? I must've missed the article.

Because none of the issues impacting RAID 5 on spinning rust exists on SSD. There are no UREs, rebuild times are practically instantaneous, drive failures were never a factor for serious consideration and the leap in IOPS is so enormous that the performance caveats to RAID 5 are lost in the ability to go from measuring per drive IOPS in the hundreds to the hundreds of thousands.

DustinB3403

Ah well that makes a lot more sense.

scottalanmiller

And that is a huge part of the cost savings... you only need N+1 drives with SSD, not N*2. So tons more performance, many fewer drives. That lends itself to tons of cost savings.

And because cost effective 2TB SSDs are available now, you can use four of those in RAID 5 and move to a small 1U chassis for all of this!

scottalanmiller

But all of this distracts us from the real solution.... no external storage. No matter how good we can make the external NAS, it's still a bad solution compared to going down to a single server and using internal drive bays.

DustinB3403

How much do you want to bet that the SAN that is being proposed will be on Spinning Rust? I don't have any details yet, but will fill you in when I get them (likely when everything has already been bought . . . )

scottalanmiller

@DustinB3403 said:

How much do you want to bet that the SAN that is being proposed will be on Spinning Rust?

I would guarantee it. People selling that stuff make no margins on disks, which is why they sell the cheapest disks with RAID 5 passing the risk to the customer and keeping the spend for the things with the margins, like the SAN chassis.